Patent · US Active

Systems and methods of characterizing process-induced wafer shape for process control using CGS interferometry

US9935022B2 · kind B2 · utility

2Cited by
15References
23Claims
0Family size

Assignee

Inventor

Key dates

Filing dateNov 29, 2016
Grant dateApr 3, 2018
Priority date—
Expiry dateNov 29, 2036

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L2223/54453
  • WIPO fieldMeasurement
  • WIPO sectorInstruments

Abstract

Systems and methods of characterizing wafer shape using coherent gradient sensing (CGS) interferometry are disclosed. The method includes measuring at least 3×106 data points on a wafer surface using a CGS system to obtain a topography map of the wafer surface. The data are collected on a wafer for pre-processing and post-processing of the wafer, and the difference calculated to obtain a measurement of the effect of the process on wafer surface shape. The process steps for processing the same wafer or subsequent wafers are controlled based on measured process-induced change in the wafer surface shape in order to improve the quality of the wafer processing.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.